23 Examples (1) Calculate the pH for each of the following solutions.1.0 × 10–4 M H+b) M OH–

24 (2) The pH of a solution is 5.85. What is the [H+] for this solution?

25 (3) Consider an aqueous solution of 2. 0 × 10–3 M HCl. What is the pH(3) Consider an aqueous solution of 2.0 × 10–3 M HCl. What is the pH? *If the solution was 2.0 × 10–3 M HNO2, a weak acid, you can’t take the same approach. Why?

26 Buffered Solutionsresists a change in its pH when either an acid or a base has been added.Presence of a weak acid and its conjugate base buffers the solution.

27 Characteristics of Buffered SolutionsThe solution contains a weak acid HA and its conjugate base A–.The buffer resists changes in pH by reacting with any added H+ or OH– so that these ions do not accumulate.Any added H+ reacts with the base A–.H+(aq) + A–(aq) → HA(aq)4. Any added OH– reacts with the weak acid HA.OH–(aq) + HA(aq) → H2O(l) + A–(aq)